Disclosed herein are methods for preparing components suitable for use in phase change inks. More specifically, disclosed herein are processes for preparing tetra-amide compounds suitable as components in phase change ink carriers. One specific embodiment is directed to a process for preparing a tetra-amide which comprises carrying out a condensation reaction between a diacid, a monoacid, and a diisocyanate, thereby forming a tetra-amide. Another specific embodiment is directed to a process for preparing a phase change ink composition which comprises (a) carrying out a condensation reaction between a diacid, a monoacid, and a diisocyanate, thereby forming a tetra-amide; and (b) admixing the tetra-amide thus formed with a colorant, thereby forming a phase change ink.
In general, phase change inks (sometimes referred to as “hot melt inks”) are in the solid phase at ambient temperature, but exist in the liquid phase at the elevated operating temperature of an ink jet printing device. At the jet operating temperature, droplets of liquid ink are ejected from the printing device and, when the ink droplets contact the surface of the recording substrate, either directly or via an intermediate heated transfer belt or drum, they quickly solidify to form a predetermined pattern of solidified ink drops. Phase change inks have also been used in other printing technologies, such as gravure printing, as disclosed in, for example, U.S. Pat. No. 5,496,879 and German Patent Publications DE 4205636AL and DE 4205713AL, the disclosures of each of which are totally incorporated herein by reference.
Phase change inks for color printing typically comprise a phase change ink carrier composition which is combined with a phase change ink compatible colorant. In a specific embodiment, a series of colored phase change inks can be formed by combining ink carrier compositions with compatible subtractive primary colorants. The subtractive primary colored phase change inks can comprise four component dyes, namely, cyan, magenta, yellow and black, although the inks are not limited to these four colors. These subtractive primary colored inks can be formed by using a single dye or a mixture of dyes. For example, magenta can be obtained by using a mixture of Solvent Red Dyes or a composite black can be obtained by mixing several dyes. U.S. Pat. No. 4,889,560, U.S. Pat. No. 4,889,761, and U.S. Pat. No. 5,372,852, the disclosures of each of which are totally incorporated herein by reference, teach that the subtractive primary colorants employed can comprise dyes from the classes of Color Index (C.I.) Solvent Dyes, Disperse Dyes, modified Acid and Direct Dyes, and Basic Dyes. The colorants can also include pigments, as disclosed in, for example, U.S. Pat. No. 5,221,335, the disclosure of which is totally incorporated herein by reference. U.S. Pat. No. 5,621,022, the disclosure of which is totally incorporated herein by reference, discloses the use of a specific class of polymeric dyes in phase change ink compositions.
Phase change inks have also been used for applications such as postal marking, industrial marking, and labelling.
Phase change inks are desirable for ink jet printers because they remain in a solid phase at room temperature during shipping, long term storage, and the like. In addition, the problems associated with nozzle clogging as a result of ink evaporation with liquid ink jet inks are largely eliminated, thereby improving the reliability of the ink jet printing. Further, in phase change ink jet printers wherein the ink droplets are applied directly onto the final recording substrate (for example, paper, transparency material, and the like), the droplets solidify immediately upon contact with the substrate, so that migration of ink along the printing medium is prevented and dot quality is improved.
Compositions suitable for use as phase change ink carrier compositions are known. Some representative examples of references disclosing such materials include U.S. Pat. No. 3,653,932, U.S. Pat. No. 4,390,369, U.S. Pat. No. 4,484,948, U.S. Pat. No. 4,684,956, U.S. Pat. No. 4,851,045, U.S. Pat. No. 4,889,560, U.S. Pat. No. 5,006,170, U.S. Pat. No. 5,151,120, U.S. Pat. No. 5,372,852, U.S. Pat. No. 5,496,879, European Patent Publication 0187352, European Patent Publication 0206286, German Patent Publication DE 4205636AL, German Patent Publication DE 4205713AL, and PCT Patent Application WO 94/04619, the disclosures of each of which are totally incorporated herein by reference. Suitable carrier materials can include paraffins, microcrystalline waxes, polyethylene waxes, ester waxes, fatty acids and other waxy materials, fatty amide containing materials, sulfonamide materials, resinous materials made from different natural sources (tall oil rosins and rosin esters, for example), and many synthetic resins, oligomers, polymers, and copolymers.
U.S. Pat. No. 6,133,353 (Bui et al.), the disclosure of which is totally incorporated herein by reference, discloses a solubilizing agent and a compound made by reacting selected nucleophiles, including fatty acid reactants and amines with an isocyanate. The addition of the isocyanate and the different nucleophiles will create a di-urethane tetra-amide solubilizing agent product. The polyamide-solubilizing agent is useful as an ingredient in a phase change solid imaging material and as carrier compositions used to make phase change ink jet inks.
U.S. Pat. No. 6,528,613 (Bui et al.), the disclosure of which is totally incorporated herein by reference, discloses a solubilizing agent and a compound made by reacting selected nucleophiles, including fatty acid reactants and amines with an isocyanate. The addition of the isocyanate and the different nucleophiles will create a di-urethane tetra-amide solubilizing agent product. The polyamide-solubilizing agent is useful as an ingredient in a phase change solid imaging material and as carrier compositions used to make phase change ink jet inks.
U.S. Pat. No. 4,830,671 (Frihart et al.), the disclosure of which is totally incorporated herein by reference, discloses an ink composition having the properties of stability and uniformity of performance under ink jet printing conditions and desired printing properties which can be obtained with hot melt ink compositions consisting of a resinous binder comprised of a compound of the formula wherein R1 represents a polymerized fatty acid residue with two carboxylic acid groups removed, R2 and R3 are the same or different and each represent an alkylene with up to 12 carbon atoms, a cycloalkylene with 6 to 12 carbon atoms, an arylene with 6 to 12 carbon atoms, or an alkarylene with 7 to 12 carbon atoms, and R4 and R5 are the same or different and each represents an alkyl having up to 36 carbon atoms, a cycloalkyl having up to 36 carbon atoms and aryl having up to 36 carbon atoms, or an alkaryl having up to 36 carbon atoms, said resinous binder having a melt viscosity of less than 250 CPS at 50° C. and a colorant distributed through the resinous binder in an effective amount sufficient to impart a predetermined color to the resulting hot melt ink composition.
U.S. Pat. No. 5,194,638 (Frihart et al.), the disclosure of which is totally incorporated herein by reference, discloses a resinous binder for use in hot melt ink compositions, which ink compositions may be used in hot melt ink jet printing applications. The resinous binder has a melt viscosity of 250 cps or less at 150° C., is sufficiently transparent to allow a colorant to be distributed through the resinous binder in an amount effective to impart a pre-determined color to the resulting hot melt ink composition, and has a blocking temperature greater than 100° C.
U.S. Pat. No. 5,645,632 (Pavlin), the disclosure of which is totally incorporated herein by reference, discloses solid diesters for hot-melt inks which are prepared by reaction of polymerized fatty acid with long chain primary monohydric alcohols, optionally in the presence of diamine. The long chain alcohols have at least about 20 carbon atoms, and preferably have 24 or more carbon atoms. The esterification of liquid polymerized fatty acid with monohydric alcohol provides a diester that is solid at room temperature and has a melting point of less than about 150° C. The diester can be formulated with colorants and/or other image-producing materials to provide an ink for hot-melt printing, e.g., hot-melt ink jet, gravure or intaglio printing.
U.S. Pat. No. 6,174,937 (Banning et al.), the disclosure of which is totally incorporated herein by reference, discloses a phase change ink comprising a material of the formula wherein X1, X2, X3, and X4 are segments comprising atoms selected from groups V and VI of the periodic table; wherein at least one R1 and R5 comprises at least 37 carbon units; and wherein R2, R3, and R4 each comprise at least one carbon unit. The invention further encompasses a composition of matter, as well as methods of reducing coefficients of friction of phase change ink formulations.
U.S. Pat. No. 4,889,560 (Jaeger et al.), the disclosure of which is totally incorporated herein by reference, discloses a phase change ink carrier composition combined with a compatible colorant to form a phase change ink composition. A thin film of substantially uniform thickness of that phase change ink carrier composition, and the ink produced therefrom, has a high degree of lightness and chroma. The thin films of a substantially uniform thickness of the ink composition are also rectilinearly light transmissive. The carrier composition is preferably a fatty amide-containing compound.
U.S. Pat. No. 5,372,852 (Titterington et al.), the disclosure of which is totally incorporated herein by reference, discloses a phase change ink composition that is indirectly applied to a substrate by raising the temperature of the phase change ink composition to form a liquid phase change ink composition, applying droplets of the phase change ink composition in a liquid phase to a liquid intermediate transfer surface on a solid support in a pattern using a device such as an ink jet printhead, solidifying the phase change ink composition on the liquid intermediate transfer surface, transferring the phase change ink composition from the liquid intermediate transfer surface to the substrate, and fixing the phase change ink composition to the substrate. The phase change ink composition is malleable when the ink is transferred from the intermediate transfer surface to the substrate and is ductile after the ink has been transferred to the substrate and cooled to ambient temperature to preclude the ink from crumbling and cracking.
U.S. Pat. No. 5,260,483 (Davis et al.), the disclosure of which is totally incorporated herein by reference, discloses methods of producing N-aryl amides which comprise reacting an aromatic isocyanate compound with substantially anhydrous carboxylic acid and recovering the resulting N-aryl amide. Additionally, or alternatively, methods of forming N-aryl amides comprise reacting an aromatic isocyanate compound with substantially anhydrous carboxylic acid in the presence of an anhydrous hydrogen halide or hydrolytically unstable halide compound and recovering the resulting N-aryl amide. These reactions may occur in the presence of an aprotic solvent.
U.S. Pat. No. 4,001,186 (Onder), the disclosure of which is totally incorporated herein by reference, discloses the use of certain catalysts that provide for an improved process for the preparation of soluble polyimides, polyamides, and polyamideimides. The catalysts are alkali metal salts of formula MOR, wherein R represents alkyl or aryl and M represents an alkali metal. The improved process comprises reacting organic diisocyanates with polycarboxylic compounds consisting of tetracarboxylic acids or the intramolecular dianhydrides thereof, tricarboxylic acids or the monoanhydrides thereof, dicarboxylic acids, and mixtures thereof, in the presence of said catalysts. The polymers are obtained in solution at low reaction temperatures and short reaction times thereby avoiding side-reactions which otherwise would be detrimental to polymer molecular weight and ultimate polymer properties.
U.S. Pat. No. 4,129,715 (Chen et al.), the disclosure of which is totally incorporated herein by reference, discloses substantially linear, segmented polyester amides which contain aromatic residues in the “hard” segments but which still possess sufficiently low melt properties to be injection moldable. The polyester amides are obtained by reacting a carboxylic acid-terminated prepolymer (derived by reacting an excess of a dicarboxylic acid with a polymeric diol of molecular weight 400 to 4000) with a stoichiometric amount of methylenebis~phenyl isocyanate) or toluene diisocyanate or mixtures of these isocyanates and, optionally, a dicarboxylic acid.
U.S. Pat. No. 4,395,531 (Toyoda et al.), the disclosure of which is totally incorporated herein by reference, discloses a process for the preparation of polyamide compounds by reacting at least one polycarboxylic acid with at least one diisocyanate in the presence of a catalyst comprising at least one mono-alkali metal salt of dicarboxylic acid. The polyamide compounds prepared by this process have a substantially linear configuration and a high degree of polymerization and, therefore, are suitable for the manufacture of fibers, films and molded articles.
U.S. Pat. No. 4,156,065 (Onder et al.), the disclosure of which is totally incorporated herein by reference, discloses an improved process for the reaction of an isocyanate (mono or poly) with a carboxylic acid or anhydride (mono or poly) to form the corresponding imide, amide or amide-imides. The improvement lies in using as the catalyst the 1-oxide, 1-sulfide or 1-hydrocarbylimino derivative of a phospholene, phospholane or phosphetane. The latter compounds are also substituted in the 1-position by a hydrocarbyl (C1-12) or halohydrocarbyl (C1-12) and may additionally carry one or more halo, lower-alkoxy, phenoxy, lower-hydrocarbyl or halo-substituted hydrocarbyl groups on the ring carbon atoms.
U.S. Pat. No. 4,061,622 (Onder), the disclosure of which is totally incorporated herein by reference, discloses the use of certain catalysts that provide for an improved process for the preparation of soluble polyimides, polyamides, and polyamideimides. The catalysts are alkali metal salts of formula MOR, wherein R represents alkyl or aryl and M represents an alkali metal. The improved process comprises reacting organic diisocyanates with polycarboxylic compounds consisting of tetracarboxylic acids or the intramolecular dianhydrides thereof, tricarboxylic acids or the monoanhydrides thereof, dicarboxylic acids, and mixtures thereof, in the presence of said catalysts. The polymers are obtained in solution at low reaction temperatures and short reaction times thereby avoiding side-reactions which otherwise would be detrimental to polymer molecular weight and ultimate polymer properties.
U.S. Pat. No. 4,066,585 (Schepp et al.), the disclosure of which is totally incorporated herein by reference, discloses intaglio and flexographic printing processes employing solvent-free inks, solid at room temperature but molten at printing temperatures, and inks suitable therefor, said inks comprising a pigment and a thermoplastic binder having a softening point between 90° C. and 160° C., said binder comprising a synthetic polyamide resin or synthetic polyesteramide resin, each resin being the condensation product of (1) an acid component comprising a dimerized fatty acid and a monocarboxylic acid and (2) an amine component comprising a diamine and, in the case of the polyesteramide resin, additionally comprising a diol and/or alkanolamine.
U.S. Pat. No. 3,622,604 (Drawert et al.), the disclosure of which is totally incorporated herein by reference, discloses synthetic polyamides, useful as binders in the formulation of printing inks, formed between a dimeric fatty acid, an unsubstituted lower aliphatic monocarboxylic acid, ethylene diamine, and certain aromatic, cycloaliphatic, and other aliphatic diamines, including aliphatic ether diamines, and methods for preparing such amides.
U.S. Pat. No. 4,417,002 (Liessem), the disclosure of which is totally incorporated herein by reference, discloses a process wherein a carboxylic acid or carboxylate is reacted with an isocyanate to produce gas which is used to give a blowing action in the manufacture of a foam plastics material, especially foam polyurethane. Preferably formic acid or a formate is used.
“The Condensation Reaction Between Isocyanates and Carboxylic Acids. A practical Synthesis of Substituted Amides and Anilides,” I. S. Blagbrough et al., Tetrahedron Letters, Vol. 27, No. 11, pp. 1251-1254 (1996), the disclosure of which is totally incorporated herein by reference, discloses that addition of a carboxylic acid to an isocyanate initially yields the mixed acid anhydride, decarboxylation of which leads to the N-substituted amide. The conversion of acid into amide was shown to proceed similarly for both aliphatic and aromatic carboxylic acids with a range of substituted isocyanates.
The Chemistry of Amides, Ed. J. Zabicky, p. 155 (Interscience Publishers 1970), the disclosure of which is totally incorporated herein by reference, discloses reactions between isocyanates and carboxylic acids.
K. B. Onder et al., “Thermoplastic Copolyamides from 4,4′-Methylene bis(Phenyl Isocyanate),” Polymer Preprints, 21(2), p. 132 (1980), the disclosure of which is totally incorporated herein by reference, discloses the synthesis of aromatic diamine based polyamides using aromatic diisocyanates and dicarboxylic acids.
“Synthesis of Polymers from Isocyanates in Polar Solvents,” H. Ulrich, J. Polymer Sci.: Macromolor Reviews, Vol. 11, 93-133 (1976), the disclosure of which is totally incorporated herein by reference, discloses the preparation of various kinds of polymers from isocyanates.
Preparative Methods of Polymer Chemistry, 2nd Ed., W. Sorenson, p.102 (Interscience Publishers 1969), the disclosure of which is totally incorporated herein by reference, discloses the preparation of polyamides from diisocyanates and dicarboxylic acids.
Polyurethanes: Chemistry and Technology, Part I, J. H. Saunders & K. C. Frish, Interscience Publishers, p. 79 and p. 187 (John Wiley & Sons 1962), the disclosure of which is totally incorporated herein by reference, discloses reactions between isocyanates and carboxylic acids.
In many known methods for preparing tetra-amides, such as those which entail condensation reactions between acids and ethylene diamine, the reaction must be carried out at relatively high temperatures, typically about 200° C. or higher. In addition, these reactions generate a hazardous mixture of water (as a result of the condensation) and ethylene diamine.
Accordingly, while known compositions and processes are suitable for their intended purposes, a need remains for improved phase change inks. In addition, a need remains for improved processes for preparing phase change inks. Further, a need remains for improved processes for preparing tetra-amide compounds. Additionally, a need remains for processes for preparing tetra-amide compounds that can be carried out at desirably low temperatures. There is also a need for processes for preparing tetra-amide compounds that do not generate toxic or hazardous materials. There is also a need for processes for preparing tetra-amide compounds that enable desirably high yields under relatively mild reaction conditions.